Unknown TI logic series

Rod Smallwood rodsmallwood at btconnect.com
Sat Dec 18 07:04:09 CST 2010

The strange number may well have been there to prevent them being resold as
full spec 74 series parts. 

As to TI not selling untested parts. Well go look at a DEC board full of TTL
and tell me who made them. Hint DEC 100% tested all bought out
semiconductors and in many cases put their own numbers on them.  

If you have your own testing facility why buy tested parts?  

Rod Smallwood

-----Original Message-----
From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org]
On Behalf Of Shoppa, Tim
Sent: 17 December 2010 19:14
To: cctalk at classiccmp.org
Subject: Re: Unknown TI logic series

> They are interesting, but no more than weird numbers on semicustom
> devices. Motorola does the same thing, with their SC series of parts
> (not MC or XC)..

I tend to come in on this side too, these funny series are
Effectively TI-supplied "house numbers".

They may be different than stock SN7400 TTL or whatever DTL in minor or
Major ways but that was an agreement between the customer and TI.

I've seen the innards of DTL and TTL based calculators, and to think that
They would work with rejects or floor sweepings is unreasonable. If
Anything I would think that the house-numbered part would have some specs
And others loosened to produce something most manufacturable. And isn't
That the reason for house numbers to begin with? (e.g. not purely


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